1. Field of the Invention
The present invention relates to a device for use in a continuous casting process and more particularly to a modular mold scaffold for billets and the like which forms a portion of a continuous casting mold which includes a plurality of mold modules which can be rather easily and precisely assembled to a predetermined casting radius.
2. Description of the Prior Art
Continuous casting of billets involves a continuous flow of molten steel from a ladle or tundish into a billet mold formed from a plurality of segments, connected together to form a predetermined casting radius. For example, 26 foot, 30 foot and 40 foot casting radii are known. The molten steel is cooled, and solidified as it passes through the various segments of the continuous caster. In a billet caster the molten steel from the ladle or tundish is formed into a billet in a first segment by a water cooled billet mold. At this stage of the continuous casting process, the billet leaves the billet mold with a molten center. The billet is continuously cooled as it passes through downstream segments of the continuous caster. The various downstream segments contain the solidified outer shell of the billet while additional cooling is provided to cool the molten center.
One of the downstream segments is known as a mold scaffold. The mold scaffold is directly connected to the billet mold and includes a plurality of stages through which the billet passes while additional cooling is applied. Each stage of the mold scaffold includes a plurality of rollers, for example, four rollers, for containing the outer shell of the billet as the additional cooling water is applied. In order to maintain the predetermined casting radius, each stage of the scaffold must be relatively precisely positioned and secured to a scaffold frame. This requires each of the four rolls, for example, in each of the scaffold stages to be relatively precisely aligned both horizontally and vertically as well as angularly to the casting radius. Consequently, such scaffolds are relatively expensive to manufacture.
Additionally, if a condition known as breakout occurs, an entire scaffold has been known to be replaced. A breakout condition occurs when the solidified shell of the billet ruptures which causes a flow of the molten steel in the center of the billet to break out and flow all over the particular segment at which the breakout occurs. When breakout occurs in a mold scaffold, one or more stages of the mold scaffold may be covered with molten steel which solidifies, thus necessitating removal of the mold scaffold to attempt to remove the molten steel with a burning torch, for example. However, in some cases when breakout results in molten metal covering the frame, which may be of unitary design, as well as the rollers, it is sometimes difficult if not impossible to clean the scaffold and realign it for subsequent use.